Mascara brush



FIG. 1 is a perspective view thereof;

FIG. 2 is a front view, the rear view is the same thereof;

FIG. 3 is a right side view, the left side view is the same thereof;

FIG. 4 is a top view thereof; and,

FIG. 5 is a bottom view thereof.

The ornamental design for a mascara brush, as shown and described.